üEngineers have now assembled the first major
piece of core stage hardware for NASA’s Space Launch System (SLS) rocket which
is designed to herald a new era of exploration beyond low-Earth orbit.

Context:

üEngineers have now assembled the first major
piece of core stage hardware for NASA’s Space Launch System (SLS) rocket

üIt is designed to herald a new era of
exploration beyond low-Earth orbit, launching crew and cargo on deep space
exploration missions to the Moon, Mars and beyond.

üIt now is
ready to be joined with other hardware for Exploration Mission-1, the first
integrated flight of SLS and the Orion spacecraft.

üThe 212-foot-tall core stage, referred to as the
“backbone” of the rocket by NASA, will contain the SLS rocket’s four RS-25
rocket engines, propellant tanks, flight computers and much more.

üThough the smallest part of the core stage, the
forward skirt will serve two critical roles.

üIt will
connect the upper part of the rocket to the core stage and house many of the
flight computers, or avionics.

ü“Completion of the core stage forward skirt is a
major step in NASA’s progress to the launch pad.

üWe’re putting into practice the steps and
processes needed to assemble the largest rocket stage ever built.

üWith the forward skirt, we are improving and
refining how we’ll conduct final assembly of the rest of the rocket.

üAs part of forward skirt testing, the flight
computers came to life for the first time as NASA engineers tested critical avionic
systems that will control the rocket’s flight.

üLocated throughout the core stage, the avionics
are the rocket’s “brains,” controlling navigation and communication during
launch and flight.

üIt is
critical that each of the avionics units is installed correctly, work as
expected and communicate with each other and other components, including the
Orion spacecraft and ground support systems.

ü“It was amazing to see the computers come to
life for the first time,” said Lisa Espy, lead test engineer for SLS core stage
avionics.

ØOrbit: An orbit is a regular,
repeating path that one object in space takes around another one

ØHeliocentric orbit: An orbit
around the Sun. In the Solar System, all planets, comets, and asteroids are in
such orbits, as are many artificial satellites and pieces of space debris.

ØGeocentric orbit: An orbit around
the planet Earth, such as that of the Moon or of artificial satellites.

ØLow Earth orbit (LEO):Low earth
orbits (LEO) are satellite systems used in telecommunication, which orbit between
400 and 1,000 miles above the earth's surface.

ØGeosynchronous orbit (GSO): A
geosynchronous orbit is a high Earth orbit that allows satellites to match
Earth's rotation. Located at 22,236 miles (35,786 kilometers) above

ØGeostationary orbit (GEO): A
geostationary orbit, often referred to as a geosynchronous equatorial orbit
(GEO), is a circular geosynchronous orbit 35,786 km (22,236 mi) above Earth's
equator and following the direction of Earth's rotation.

·Geostationary orbits are also geosynchronous,
but not all geosynchronous orbits are geostationary.

· A geostationary orbit stays exactly above
the equator, whereas a geosynchronous orbit may swing north and south to
cover more of the Earth's surface.

· Both complete one full orbit of Earth per
sidereal day

ØPolar orbit:An orbit that passes
above or nearly above both poles of the planet on each revolution. Therefore,
it has an inclination of (or very close to) either 90 degrees or -90 degrees.

ØPolar Sun-synchronous orbit (SSO):
A nearly polar orbit that passes the equator at the same local solar time on
every pass. Useful for image-taking satellites because shadows will be the same
on every pass.

ØGeostationary or Geosynchronus Transfer
orbit (GTO):An elliptic orbit where the perigee is at the altitude of a
low Earth orbit (LEO) and the apogee at the altitude of a geostationary orbit.

Expected prelims question:

Communication satellites are generally placed in

a)Low earth orbit

b)Middle earth orbit

c)High earth orbit

d)None of the above

Ans - a

Expected mains question:

Discuss the various types of orbits. Add a note on why many countries uses varied orbits to launch its satellites.